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We report the depredation by a single Eastern Barn Owl Tyto javanica delicatula on prospecting White-faced Storm Petrels Pelagodroma marina during the re-establishment phase of a colony on Big Island, off Port Kembla, New South Wales, Australia in 2018. Storm petrels were likely extirpated from this colony 56 years previously when invasive weeds rendered their habitat inaccessible. Restoration of vegetation together with storm petrel call broadcasting, commencing in 2014, resulted in significant increases in prospecting numbers, culminating in breeding (three pairs) in the 2017/18 austral summer season. A significant depredation event (> 59 adults) occurred between August and September 2018, providing a set-back to colony establishment. Previously, barn owl depredation on Big Island had been limited to Silver Gulls Chroicocephalus novaehollandiae as prey. However, in the 2018/19 season, the gulls commenced nesting later than usual. The delay appeared to cause the owl to switch target prey. Despite the intense depredation pressure, at least two pairs of storm petrels attempted to breed in the 2018/19 season and 10 birds were trapped and banded at the commencement of the 2019/20 season. Discovery of the mainland roost of the owl was attempted between the two seasons, and its potential death by car strike was investigated. Our findings show that even a single individual predator can have significant impacts on seabird colonies establishing or re-establishing in island environments, especially those under restoration. [ABSTRACT FROM AUTHOR]

We present the first tracked movements of the medium-sized tropical White Tern Gygis alba, using Global Location Sensors (GLS), from a breeding colony on Lord Howe Island, South Pacific, Australia. The tracking period encompassed pre-breeding in 2018 to potential chick provisioning in the following season. Terns remained near Lord Howe Island during breeding, with some pre-egg-laying and post-nestfailure trips 1 000 km distant. The average departure date from Lord Howe Island was 08 April (range: 21 March–22 April). The tern’s migration route was northwest towards the eastern Australian coast, skirting the Great Barrier Reef. Terns then spent the non-breeding period (50% utilisation distribution) in the northwestern Coral Sea bounded by the New Guinea archipelago to the north and North Queensland, Australia, to the west. The mean transit time to the core non-breeding areas was five days (standard deviation ± 2.5 d). The core nonbreeding area was 2 200 km from Lord Howe Island. The mean time spent in the core non-breeding area was 93 d (± 10 d). The return passage completed a clockwise journey with a mean passage time of 12 d (± 3.8 d) and an average arrival on Lord Howe Island of 18 August (range: 08 August–02 September). Over 51% of their core foraging and non-breeding areas were within dedicated marine park networks. We documented the day visits to the island and approximate incubation shifts and nest attendance from changes in light levels of GLS devices. We determined, using saltwater immersion data, that the species exhibited almost no contact with the sea surface during darkness. Peak activity during daylight hours commenced at 12h00, probably indicating resting after foraging at sea. From the limited samples, instrumenting of the terns did not appear to impede breeding attempts during the 14 months of attachment. [ABSTRACT FROM AUTHOR]

On 11 July 2019, during the Rodent Eradication Program on Lord Howe Island using aerial and ground rodentbaiting, the recovery of dead non-target birds included a recently dead boobook Ninox sp. found on a resident’s property. Two Tyto species were also recovered. Despite automated sound-recording equipment stationed within the forests of the Island, no records of Ninox vocalisations were made before discovery of the boobook specimen; however, two instances of Ninox owl calls were reported anecdotally within The Settlement. There was speculation from some Island residents that the recovered boobook could have been an individual of the extinct endemic subspecies, the Lord Howe Boobook N. novaeseelandiae albaria. The boobook was forwarded to the Australian Museum for further visual scrutiny, collection of morphometric data, DNA analysis, and preparation for the Australian Museum collection. There was overlap in plumage and morphological measurements between both the Tasmanian Boobook (N. leucopsis) and the nominate Tasman Morepork from New Zealand (N. n. novaeseelandiae), but the specimen was distinct from the larger Australian mainland N. boobook. DNA analysis provided conclusive evidence that the bird was a male N. leucopsis, exhibiting an overall clean-white spotted pattern and darker brown coloration. The occurrence of a Ninox species on Lord Howe Island is the first record in more than 50 years and should prompt further exploration of the dispersal and possible migration of boobooks from Tasmania. [ABSTRACT FROM AUTHOR]

Globally, seabird populations have been in decline due to multiple threats throughout their range. Separating simultaneous pressures is challenging and can require significant amounts of data over long periods of time. We use spatial contrasts to investigate the relative importance of several drivers for the purported decline in a species listed as in decline as an example species, the Flesh-footed shearwater (Ardenna carneipes). On Lord Howe Island in the Tasman Sea, Australia, this seabird suffers from habitat loss due to housing development, intensive mortality in fisheries, plastic ingestion, and roadkill due to vehicular traffic on its breeding island. We repeated a quantitative survey of the population to ascertain whether the decline previously reported had continued and to evaluate the purported mortality sources (Reid et al. in PLoS ONE 8(4):e58230, 2013, Lavers et al. in Global Ecol Conserv 17:e00579, 2019). We measured burrow density, area of occurrence, occupancy and breeding success, integrating them with previous surveys using a Bayesian statistical model to generate longer term estimates of demographic rates. We used spatial patterns to test whether mortality on roads or proximity to human habitation was influencing population demographics. In contrast to predictions, we found the population had stabilised or increased. Characteristics such as burrow occupancy and breeding success showed little pattern, with weak evidence for impacts from road mortality and housing development. Such a data-rich approach is substantially more informative and can better support seabird conservation and management efforts does require more field-time and additional equipment than most contemporary surveys, the data is substantially more informative and can better clarify the results of efforts in seabird conservation and management. [ABSTRACT FROM AUTHOR]

Abstract: Little is known of the Endangered Lord Howe Island Cockroach Panesthia lata Walker, , other than that it disappeared from Lord Howe Island following the introduction of ship rats Rattus rattus (Linnaeus, 1758) in 1918. With a rodent‐eradication programme being planned for Lord Howe Island, an opportunity exists to reintroduce P. lata once rodents have been removed. Previous brief surveys of other islands within the Lord Howe Group have found that P. lata still occurs on some of these islands. In this study, further surveys were conducted on two of those islands (Blackburn and Roach) to gain a better understanding of the distribution and abundance of P. lata there and to investigate potential survey techniques. Brief observations were also made of the behaviour and ecology of the species. Extrapolation from survey plots showed that although 60% of the estimated population of 10 000 individuals on Blackburn Island were living beneath the sole Banyan Ficus macrophylla Desf. tree, P. lata was widely distributed across the island, utilising both native and exotic vegetation, including the introduced Rhodes Grass Chloris gayana Kunth. On Roach Island, the bulk of the estimated population of 3500 individuals occurred within Leafy Flat Sedge Cyperus lucidus R. Br. habitat. Panesthia lata seemingly spends considerable time sheltering within refuges rather than foraging on the surface; consequently, population estimates based on surface counts are underestimates. Improving either the accuracy or precision of these counts risks damaging individuals and their habitat. Mark‐recapture techniques were not applicable for assessing the abundance of this species, but trials of novel attraction stations indicated that such devices could be useful for monitoring distribution and gross fluctuations in population size. Panesthia lata appears to feed on any dead vegetation, but primarily leaves. Individuals were relatively sedentary overnight, sheltering by day under any object that provided the appropriate microenvironment. Soil characteristics in areas where P. lata sheltered were significantly modified, suggesting that this species may play an important role in soil conditioning and nutrient cycling. Maintaining the rodent‐free status of islands on which P. lata occurs is a high priority for this species. [ABSTRACT FROM AUTHOR]

Aim Anthropogenic activities alter and constrain the structure of marine ecosystems with implications for wide-ranging marine vertebrates. In spite of the environmental importance of vast oceanic ecosystems, most conservation efforts mainly focus on neritic areas. To identify relevant oceanic areas for conservation, we assessed the year-round spatial distribution and spatio-temporal overlap of eight truly oceanic seabird species of gadfly petrels ( Pterodroma spp.) inhabiting the Atlantic Ocean. Location Atlantic Ocean. Methods Using tracking data (mostly from geolocators), we examined year-round distributions, the timing of life-cycle events, and marine habitat overlap of eight gadfly petrel species that breed in the Atlantic Ocean. Results We compiled 125 year-round tracks. Movement strategies ranged from non-migratory to long-distance migrant species and from species sharing a common non-breeding area to species dispersing among multiple non-breeding sites. Gadfly petrels occurred throughout the Atlantic Ocean but tended to concentrate in subtropical regions. During the boreal summer, up to three species overlapped spatio-temporally over a large area around the Azores archipelago. During the austral summer, up to four species coincided in a core area in subtropical waters around Cape Verde, and three species shared habitat over two distinct areas off Brazil. The petrels used many national Exclusive Economic Zones, although they also exploited offshore international waters. Main conclusions Tracking movements of highly mobile vertebrates such as gadfly petrels can provide a powerful tool to evaluate and assess the potential need for and location of protected oceanic areas. As more multispecies, year-round data sets are collected from wide-ranging vertebrates, researchers and managers will have greater insight into the location of biodiversity hotspots. These can subsequently inform and guide marine spatial planning efforts that account for both conservation and sustainable use of resources such as commercial fisheries. [ABSTRACT FROM AUTHOR]

A translocation of wild-bred and captive-bred Little Penguin Eudyptula minor fledglings was trialled to reinforce (augment) an urban population of this species in Sydney Harbour, Australia. Over three breeding seasons (2004/05 to 2006/07), a total of 44 wild-bred fledglings from nearby Lion Island and 19 captive-bred fledglings from local zoos were translocated to Store Beach, North Harbour, within Sydney Harbour. All translocated birds were implanted with a numbered microchip before release. During the same period, the North Harbour colony produced at least 327 fledglings, of which 113 were implanted with microchips prior to fledging. The North Harbour colony was monitored between 2005 and 2013 to identify any returning translocated or locally wild-bred birds. Three translocated wild-bred birds and 12 locally wild-bred birds are known to have returned to North Harbour, but no translocated captive-bred birds. One translocated wild-bred bird returned to Store Beach while the remaining two returned to adjacent headlands. The number of pairs of Little Penguin breeding on Store Beach, where threats are intensively managed, has increased from one in 2004 to nine in 2013. This study demonstrated that translocation of wild-bred fledglings is feasible. However, because of naturally low return rates, translocations of Little Penguins need to involve a large number of individuals, preferably taken from a sizeable donor colony, to be effective in reinforcing a threatened or declining population. The effectiveness of releasing captive-bred Little Penguins has yet to be demonstrated. [ABSTRACT FROM AUTHOR]

Context. For the past 50 years, rodent eradications have been conducted worldwide to reverse the devastating impacts of introduced rodents on island species. However, few studies have quantitatively measured the effects of rodent eradications on native species. Aims. This study investigated the effects of a rodent eradication on Lord Howe Island on two native birds. Methods. To mitigate the risk of Lord Howe currawongs being poisoned during baiting operations, 30-40% of the population were taken into captivity during baiting, while the remaining currawongs were left in the wild. We studied currawong survival, nesting density and breeding success pre- and post-eradication to test how the baiting, a period in captivity, and the removal of rodents affected currawongs. We also investigated breeding success of white terns as they were expected to benefit from the eradication due to predator reduction. Key results. We found that many currawongs left in the wild disappeared during the baiting period and nesting densities in one part of the island were significantly lower after the eradication. These currawongs likely died of poisoning as they were not resighted for 2 years post-eradication. White tern breeding success did not increase after the rodent eradication, although their predators were largely eliminated. Conclusions. The captive management of currawongs mitigated the adverse effects of the baiting. As those currawongs that survived had high breeding success, we predict that the population will soon recover to pre-eradication size. Implications. Our study reinforces the necessity of integrating ecological monitoring as part of future eradications on islands. [ABSTRACT FROM AUTHOR]

The article discusses a study which examines the introduction, growth, and distribution of White tern on Lord Howe Island, New South Wales. Results show the distribution and abundance of breeding sites, population growth, and success of hatching, breeding, and fledgling. The predators of the species are also mentioned including Lord Howe Pied currawong and Masked owl.

This study describes and compares the pelagic distribution and migratory patterns of the two subspecies of Gould's Petrel (Pterodroma leucoptera), and contrasts data obtained from tracking birds at sea using geolocators with observational data (shipboard sightings, by-catch records and beachcast specimens). While breeding, tracked individuals of both subspecies (P. l. leucoptera and P. l. caledonica) foraged within the Tasman Sea and south of the Australian continent, with forays west into the Indian Ocean before laying. After breeding, both subspecies migrated to distinct non-breeding ranges within the eastern tropical Pacific Ocean. Observational data identified the general pattern of migration and foraging areas of the species, whereas data from geolocators provided details of routes and timing of migration, core foraging ranges, and marked spatial and temporal segregation between the two subspecies. However, by attaching geolocators only to established breeders, as is typical of studies of small and medium-sized seabirds, these devices failed to identify that non-breeding birds (pre-breeders and adults that are deferring breeding) may not follow the same migratory schedules or have the same at-sea distribution. We conclude that integrating data from electronic tracking with observational data substantially improves our understanding of the pelagic distribution of seabird populations. [ABSTRACT FROM AUTHOR]

Reducing extinction risk is a common aim of threatened species management. However, over the period 1990 to 2020, extinction risk was recently assessed as having declined in only 25 out of the 199 Australian bird taxa eligible for assessment. Here we analyse patterns that emerge from these taxa. Some of these improvements may be only temporary; the extinction risk of three taxa increased after it had initially declined. Invasive predator control on islands was the conservation intervention with greatest impact, benefitting 13 taxa (with nine of these from Macquarie Island). For four taxa, intensive management was the primary driver of reduced risk. Another four benefited from habitat protection and one from law enforcement. For seven taxa, conservation actions had no discernible effect; for two albatrosses a shift in fishing patterns may have reduced bycatch, for one, losses on the mainland meant that most birds now persist only in a stable island population and, for four taxa, reasons for changes in population trend are unknown. Never was there only one driver of reduced extinction risk with most taxa benefitting from at least five drivers. Macquarie Island was the only geographic cluster of taxa; there was little overlap among other taxa. Although the number of improvements is small, our results demonstrate that reduced extinction risk can be achieved with the right combination of targeted actions and, in some cases, serendipity. However, due to insufficient data, our ability to predict accurately the drivers of, or changes in, extinction risk for most species remains poor. Reductions in extinction risk are rare but achievable. Up to ten different factors contributed to reduced extinction risk in a taxon; there were rarely fewer than five. Extinction risk reduction had no geographical focus apart from the cluster of taxa on Macquarie Island. There is currently no widely accepted approach to classifying the many ways in which extinction risk can be reduced. Over a quarter of risk reduction examples were not the result of conservation interventions. [ABSTRACT FROM AUTHOR]

The cover image, by Raül Ramos et al., is based on the Biodiversity Research It is the time for oceanic seabirds: Tracking year‐round distribution of gadfly petrels across the Atlantic Ocean, DOI:10.1111/ddi.12569. Photo Credit: Jacob González‐Solís. [ABSTRACT FROM AUTHOR]

Procellariiformes have prolonged incubation shifts, with breeding birds enduring long periods of fasting and substantial reductions in body mass. These changes can be physically demanding and parents must balance their own energy requirements with the needs of their unhatched young. The incubation routine and associated changes in body mass of breeding Gould’s Petrel (Pterodroma leucoptera) were studied to explore the relationships between body mass, incubation shift duration and nest desertion. The incubation routine of Gould’s Petrel was similar to other Procellariiformes, although shift length was particularly long for a bird of this size. Failure to complete incubation was due to egg damage or nest desertion. Temporary egg abandonment was observed in successful as well as in failed breeders, although eggs abandoned for longer than 1 day all failed. Nest desertions generally occurred before the normal duration of the incubation shift rather than after excessively long shifts caused by the late return of the partner. We conclude that incubation success was limited by both the condition of birds at the start of the shift and their tenacity to remain until relieved by their partner. [ABSTRACT FROM AUTHOR]

We report the cross-fostering of a Wedge-tailed Shearwater chick by White-necked Petrels during the 2016/17 breeding season in the Norfolk Islands. Our finding highlights the possibility that cross-fostering of these procellariids can be used in conservation applications. [ABSTRACT FROM AUTHOR]

Pterodroma leucoptera caledonica is a subspecies of Gould's Petrel endemic to New Caledonia. Its distribution, abundance and breeding biology are poorly known. Extensive surveys of New Caledonia between 1994 and 2014 located only two breeding colonies, and a further likely, but still unconfirmed; the total estimated size of the population could be of the order of 5000–7000 breeding pairs. Nesting burrows were situated either near streams or on slopes near ridges. The breeding phenology of caledonica was similar to that of the Australian leucoptera, but with a breeding calendar that lagged that of leucoptera by 2–4 weeks depending on year and breeding parameter. Breeding success was low, with evidence of a high level of predation of eggs, chicks and adults by rats, pigs and cats. Pigs also destroyed nesting burrows. Permanent bait stations installed to control rats at one colony appeared successful, but the control of pigs and cats is much more problematic. If, as expected, the level of predation observed at one colony extends across all breeding colonies, population decline is inevitable and extinction likely in the long term. With no populations of P. l. caledonica on predator-free offshore islands, translocation to such sites may be evaluated to safeguard this subspecies. In the meantime, we recommend that the global status of Gould's Petrel Pterodroma leucoptera be upgraded from Vulnerable to Endangered. [ABSTRACT FROM AUTHOR]

On isolated islands, large arthropods can play an important functional role in ecosystem dynamics. On the Norfolk Islands group, South Pacific, we monitored the diet and foraging activity of an endemic chilopod, the Phillip Island centipede (Cormocephalus coynei), and used a stable isotope mixing model to estimate dietary proportions. Phillip Island centipede diet is represented by vertebrate animals (48%) and invertebrates (52%), with 30.5% consisting of squamates, including the Lord Howe Island skink (Oligosoma lichenigera) and Günther's island gecko (Christinus guentheri); 7.9% consisting of black-winged petrel (Pterodroma nigripennis) nestlings; and 9.6% consisting of marine fishes scavenged from regurgitated seabird meals. Centipede predation was the principal source of petrel nestling mortality, with annual rates of predation varying between 11.1% and 19.6% of nestlings. This means that 2,109–3,724 black-winged petrel nestlings may be predated by centipedes annually. Petrels produce a single offspring per year; therefore, predation of nestlings by centipedes represents total breeding failure for a pair in a given year. Our work demonstrates that arthropods can play a leading role in influencing vertebrate reproductive output and modifying trophic structures and nutrient flow in island ecosystems. [ABSTRACT FROM AUTHOR]

For most passerines, nest predation has a major impact on breeding success; however, information on the identity of nest predators is scant. In 2012, we investigated the identity of nest predators that each year depredate about 50% of the nests of 21 species in a south-east coastal bird community in New South Wales, Australia. The current study is a 2-year extension of this study and shows that at this study site (a) predation accounts for at least 90% of nest failures, (b) identified nest predators comprised two reptiles, nine birds and five mammals, (c) the suite of predators changes each season, (d) the two major predators were the Eastern Whipbird (Psophodes olivaceus) and the Fan-tailed Cuckoo (Cacomantis flabelliformis), (e) the impact of the Red Fox and Feral Cat was minimal, and (f) there was a variable and complex interaction between the parasitic cuckoos and their hosts. The data show definitively the overwhelming importance of nest predation on fledgling production, and bring to light new and important data on several aspects of the suite of nest predators. [ABSTRACT FROM PUBLISHER]

It is widely believed that predators maximise their energy intake while foraging and consume prey that are nutritionally similar. We combined GPS data loggers, miniaturised cameras, dietary sampling and nutritional geometry to examine the nutritional variability in the prey and selected diet, and foraging performance, of the masked booby (Sula dactylatra tasmani), a wild carnivore and marine top predator. Data loggers also revealed no significant differences between sexes in the foraging performance of chick-rearing adults. Females provided more food to their chicks than the males and, regardless of the nutritional variability of prey consumed, both sexes showed similar amounts of protein and lipid in their diets. Miniaturised cameras combined with nutritional analysis of prey provided, for the first time, fine-scale detail of the amounts of macronutrients consumed in each plunge dive and the overall foraging trip. Our methodology could be considered for future studies that aim to contribute to the general understanding of the behavioural and physiological mechanisms and ecological and evolutionary significance of animal foraging (e.g. energy expenditure budgets and prey selection for self- and offspring-feeding that could lead to sex-specific foraging strategies). [ABSTRACT FROM PUBLISHER]

The Fregetta storm-petrels generally are regarded to comprise two species: black-bellied storm-petrels F. tropica (monotypic) breed at Antarctic and sub-Antarctic islands (46–63°S), and white-bellied storm-petrels F. grallaria breed at south temperate islands (28–37°S), with four recognized subspecies. Confusion surrounds the status of birds at Gough Island (40°S), central South Atlantic, which have been attributed usually to a white-bellied form of black-bellied storm-petrel F. t. melanoleuca . We use cytochrome b and nuclear β-fibrinogen gene sequences to show that F. t. melanoleuca are present during the breeding season at Gough and islands in the nearby Tristan da Cunha archipelago (37°S), exhibiting limited divergence from F. t. tropica . We also show that there is greater diversity among F. grallaria populations, with eastern South Pacific F. g. segethi and F. g. titan differing by c. 0.011, and both differing from western South Pacific nominate F. g. grallaria by c. 0.059. The Tristan archipelago supports a population of F. grallaria closely allied to the nominate form, as well as a distinct form identified as F. g. leucogaster . Further research is needed to assess how F. grallaria and F. tropica segregate in sympatry at Tristan and Gough, and why this is the only location where both species have white-bellies. [ABSTRACT FROM AUTHOR]

Objectives: The objective of this study was to investigate the silver gull as an indicator of environmental contamination by salmonellae and carbapenemase-producing Enterobacteriaceae (CPE) in south-east Australia.Methods: A total of 504 cloacal samples were collected from gull chicks at three nesting colonies in New South Wales, Australia [White Bay (n = 144), Five Islands (n = 200) and Montague Island (n = 160)] and were examined for salmonellae and CPE. Isolates were tested for carbapenemase genes and susceptibility to 14 antibiotics. Clonality was determined by PFGE and MLST. Genetic context and conjugative transfer of the carbapenemase gene were determined.Results: A total of 120 CPE of 10 species, mainly Escherichia coli (n = 85), carrying the gene blaIMP-4, blaIMP-38 or blaIMP-26 were obtained from 80 (40%) gulls from Five Islands. Thirty percent of birds from this colony were colonized by salmonellae. Most isolates contained the gene within a class 1 integron showing a blaIMP-4-qacG-aacA4-catB3 array. The blaIMP gene was carried by conjugative plasmids of variable sizes (80-400 kb) and diverse replicons, including HI2-N (n = 30), HI2 (11), A/C (17), A/C-Y (2), L/M (5), I1 (1) and non-typeable (6). Despite the overall high genetic variability, common clones and plasmid types were shared by different birds and bacterial isolates, respectively.Conclusions: Our data demonstrate a large-scale transmission of carbapenemase-producing bacteria into wildlife, likely as a result of the feeding habits of the birds at a local waste depot. The isolates from gulls showed significant similarities with clinical isolates from Australia, suggesting the human origin of the isolates. The sources of CPE for gulls on Five Islands should be explored and proper measures applied to stop the transmission into the environment. [ABSTRACT FROM AUTHOR]